function greeter(person:string, times:number): string{
    let display: string = 'Hi I\'m lisiyu ';
    let res: string = 'I love you ';
    let list:number[] = [0,1,2];
    let element:number = 0 ;
    let notSure: any = 4;
    notSure = "this not sure type"
    for (let index = 0; index < list.length; index++) {
        element += list[index];
    }
    //let ret: string = display + res + person + " " + (element*times) + " times";
    let ret: any = notSure;
    return ret;
}
let user = "Meng Yanling"
let decimal:number = 3000 

document.body.textContent = greeter(user, decimal)
//console.log(greeter(user))